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Nov 2016
11:26pm, 19 Nov 2016
1,754 posts
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Canute
Hi. It has been interesting to catch-up on recent post on the thread. On the question of HR zones, I think HR is a fairly reliable guide in the upper aerobic zone but a poor guide in the lower aerobic zone where I do most of my training. I find respiratory rate and depth are a more reliable guide. I do most of my easy running at a relaxed 4 breaths per step, and some slightly more demanding running at 3 breaths per step.
I have not been posting recently because I have been very busy at work, and will continue to be busy in the near future. I have however continued running regularly, mainly very slowly because my torn knee ligaments have not healed. Overall I am still following a polarised strategy, but my only intense sessions are on the elliptical. I am not training for any particular event; simply enjoying keeping moderately fit, and especially enjoying running in the autumnal woods – though there are also days when I feel very old and cronky.
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Nov 2016
6:56pm, 22 Nov 2016
8,115 posts
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Boab
Good to hear from you Canute.
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Nov 2016
11:18pm, 22 Nov 2016
1,755 posts
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Canute
Hi Boab. I hope your running is going well.
In note that in my post above I should have said 4 steps/breath, 3 steps/breath etc.
I think that respiration is a better guide to effort that HR simply because many things influence heart rate while respiratory drive is determined directly by the level of acid in the blood. There are acidity detectors (pH sensitive nerve endings) in the walls of the large arteries in the neck. As lactic acid rises above approx 2 mmol, there is an increase in respiratory drive which is easy to perceive once you have developed an awareness of the sensation. At that stage, I semi-automatically increase breathing rate from 4 steps/ breath to 3 steps/breath. When lactic acid takes a steep upward turn around LT, I increase breathing rate from 3 steps/breath to 2 steps/breath. It is best to let this happen semi-automatically. Some people find they get muddled by conscious counting of steps and breaths. It does take a bit of deliberate focus for a period of a few weeks to develop, an awareness of the respiratory drive, but I think it is well worthwhile.
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Nov 2016
6:39am, 23 Nov 2016
8,116 posts
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Boab
I've dabbled with breaths in/out in the past Canute. It does take a bit of concentration to keep a good count going. I always find I drift off, maybe a bit like getting in the zone when meditating.  I've had to snap out of the 'zone' to remember to count breaths again. Maybe with practice you instinctively know the breaths in or out.
I agree with you that HR has it's faults, like the outside influence you mention, but also the lag. There are some companies now trying to sell power metres for running, much like cyclists as you get an instant reading of effort. I've not looked into them too much as I suspect the contraptions, ironically, will negatively affect effort due to how they work!! Do you have any thoughts on these running power metres?
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Nov 2016
1:01am, 25 Nov 2016
1,756 posts
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Canute
I have not used a running power meter, but am intrigued by all the information that they offer.
The actual power estimate is computed using a complex algorithm based on measurement of the time course of the mechanical forces exerted during running. These forces can be measured quite accurately using modern accelerometer technology. There are three main sources of mechanical energy expenditure when running: elevation the body to get airborne, overcoming braking; moving the leg forwards during swing phase. The first two can be computed fairly easily using the laws of physics but the swing cost depends on leg shape and foot trajectory. As far as I can glean from the information released by manufacturers, this computational challenge is tackled by adjusting the algorithm based on fitting the data from many runners. At fast paces, swing cost is the greatest of of the three mechanical energy costs. Therefore, the accuracy of the energy cost will only be good for an individual with leg shape and trajectory within the rage of the calibration sample,
Furthermore, there is the issue of question of metabolic efficiency: how much mechanical work that a muscle can perform per Kcal of fuel consumed. Typically only about 40% of metabolic energy consumed is converted to mechanical work
However I do not think any of the uncertainties about actual energy consumption (in Kcal) or mechanical power (in watts) matter greatly for the purpose of monitoring training. It is values relative to you own performance that matter.
Perhaps there is a more serious issue with things that change for one individual between training sessions : eg wind and terrain and I am not sure how well the current devices cope with these variables.
Nonetheless, at least on smooth terrain and light winds, I would anticipate that a well designed power meter would give a more reliable estimate of your power output and hence your effort than either HRM or estimation of respiratory effort.
For the purpose of adjusting training effort I doubt whether there is need for very high precision, and I would not buy a power meter for this purpose. Although I am fascinated by the running mechanics. I also value the simplicity of running.
However if I was ever to train seriously for a marathon again, I would consider getting one for the sake of the other mechanical variables that are measured eg variables such as leg stiffness and other indices of fatigue during long runs, in order to assess the effects of varying cadence etc, and also to monitor the efficacy of plyometric training for enhancing leg muscle resilience.
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Nov 2016
8:22am, 25 Nov 2016
10,333 posts
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Chrisull
***lurks furiously***
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Nov 2016
9:39am, 25 Nov 2016
2,473 posts
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Ninky Nonk
My fundamental issue with power/heart rate is the belief that you will train better by being in the right 'zone'. The purpose of the various devices is to as accurately position you in that zone as possible.
Couple of problems with that
Although the numbers might be precise - they are not accurate.
The zones are really so wide that you don't need to accurately position yourself in them.
The whole proposition of zone training limits training and is based on general non-individual generic parameters.
The devices can be useful to guide novices to the right sort of training efforts but after a while people should be less reliant on them. You would be foolish to rely on these items in a race - therefore why rely on them in your training.
Just a personal view for discussion. I realise many people find hr a very useful tool and have had very good results training using heart rate methods.
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Nov 2016
10:00am, 25 Nov 2016
10,336 posts
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Chrisull
"The zones are really so wide that you don't need to accurately position yourself in them. The whole proposition of zone training limits training and is based on general non-individual generic parameters. "
NN - You describe concisely my own ambivalence. We have the quotes of one or two coaches about "most people disappear into a black hole zone", yet are they really saying
"train at the bottom of zone 3 or at the top of zone 3 and they will have equal training responses"
Ergo we should train at the bottom of zone 3(zone 2, or zone 1 or zone 4), because ultimately it is less damaging/difficult to recover from (no argument on the less damaging). I'd like to see the studies that demonstrate that. And I'd be sceptical of any studies anyway because of your first point - the zones might be precise, but they aren't accurate - which is what I've been shouting loudly in other forums.
Maffe vs HRM vs Karvonen modified offer 3 completely different zones to train in for me. They cannot all be correct.
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Nov 2016
10:01am, 25 Nov 2016
10,337 posts
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Chrisull
(three different *easy* zones) - of course they offer different zones :-).
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Nov 2016
6:28pm, 25 Nov 2016
1,757 posts
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Canute
I agree with NN and Chrisull that there is no compelling evidence that precise adjustment of training intensity is essential for a distance runner. In contrast, I believe that building confidence in one’s own ability to judge effort level is worthwhile. This is part of the reason why I rely mainly on awareness of respiratory effort.
However looking back on my marathon training from years ago, I think by placing emphasis on building aerobic capacity (which is undoubtedly of major importance) I underestimated the importance of developing leg muscle resilience. Slowing down in the late stage of along race is often due to failing legs rather than failing cardiovascular capacity.
I did do some hill training, but probably would have benefitted from more hills and/or sprints and plyometrics. In those days I had little idea about how to allocate my training time to ensure optimum balance between developing aerobic capacity and leg muscle resilience. Maybe a power meter (used for retrospective analysis of change in time on stance etc over the course of a long run, rather than as a device for measuring effort during the run itself) would have been useful for planning training to optimise the balance between aerobic capacity and leg muscle resilience.
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